Wireless communication systems continue to evolve in order to provide subscribers alternative or enhanced services, and to permit more efficient use of available radio bandwidth. For example, wireless communication systems have successfully migrated from an all analog configuration (AMPS) to standards that provide digital communication such as IS-136. In such service migrations, continued support for an installed standard is generally necessary in order to maintain service for current subscribers. If services provided according to a particular standard are discontinued, then subscriber service can be disrupted while subscribers acquire new mobile stations or other hardware, or reconfigure installed hardware to conform to newly introduced requirements. Because of the disruption, inconvenience, and expense associated with service migration, service migration can prompt subscribers to consider subscribing to services offered by other service providers. Because service providers consider retaining current customers to be an important business objective, installed services continued to be offered and supported as new features or services are added.
In a typical mobile network, radio transmitters and associated antennas are remotely located at numerous cell sites, and communication with the remote cell sites is accomplished using a wired connection, typically a digital link based on, for example, a so-called T-1 level. Generally the introduction of services based on new or additional standards requires providing additional digital or other communication links to the cell sites as well as additional transmitters and antennas. The cost of additional digital links to the cell sites can be substantial, and in some cases, additional links must be installed. Thus, providing dedicated digital links or other communication links to cell sites to support each available mobile standard can be prohibitively expensive. Therefore, methods and apparatus that facilitate multi-standard operations are needed.